Refrigerating apparatus



June 23, 1942. SMITH 2,287,203

' REFRIGERATING APPARATUS r Filed Sept. 29, 1939 5 Sheets-Sheet 1 INVENTOR.

Z I FMF Al. SM/ h'.

I I a d ms ATTORNEYS.

R. M. SMITH REFRIGERATING APPARATUS June 23, 1942.

Filed Sept. 29, 1939 5 Sheets-Sheet 2 INVENTOR. P l. F 54/771.

1.: ATTORNEY-b June 23, 1942.

Filed Sept. 29, 1939 5 SheetsSheet 5 m; ATTORNEYS June 23, 1942. R. M. SMITH REFRIGERATING APPARATUS Filed Sept. 29, 1939 I 5 Sheets-Sheet 4 7/4067Z /AWI/1 r//// ll INVENTOR. Paml f. Sun/I.

,ws ATTORNEYS.

Patented June 23, 1942 REFRIGERATING APPARATUS Rolf M. Smith, Dayton, Ohio, assignor to General I vMotors Corporation, Dayton, Ohio, as corporation of Delaware Application September 29', 1939, Serial No. 297,148

8 Claims. -(CL 230-232) This invention relates to refrigerating apparatus and particularly to a motor-compressor unit for refrigerating systems.

An object of my invention is to provide an improved sealed motor-compressor unit for use in refrigerating systems.

Another object of my inventionis to provide a sealed motor-compressor unit of the type wherein a structure which carries the operating parts thereof is resiliently supported in an improved .manner within a sealed casing so as to minimize noises and eliminate damage to the structure during shipping of the unit.

Another object of my invention. is to provide a sealed motor-compressor unit of the type wherein a casing providing the sealing enclosure for operating parts of the unit forms a part of the low pressure side of a refrigerating system and wherein refrigerant entering the compressor and refrigerant discharged therefom is muiiied lowing description. In the drawings:

efllcient. quiet operating and durable unit, as will more fully appear in the course of the fol-.

Fig.-l is a horizontal section through the machine compartment of a refrigerator cabinet showing a top plan view of a refrigerant trans iating device. including a motor-compressor unit;

Fig. 3 is a transverse, vertical sectional view of a sealed motor-compressor unit included in the device shown in Figs. 1 and 2' and constructed in accordance with myinvention;

Fig. 4 is a horizontal section taken on the line 44 of Fig. 3 ina direction upwardly of the in an effective manner to reduce noises to a minimum.

A further object of my invention is to provide a sealed motor-compressor unit of the type wherein a casing providing the sealing enclosure therefor forms a part of the low pressure side of a refrigerating system and wherein a body of lubricant in the lower part of the sealed enclosure is heated by refrigerant discharged from the compressor for evaporating refrigerant therefrom to insure themaintenance of a body of substantially undiluted 011 within the casing for circulation to operating parts of the unit.

A still further object of my invention is to provide an improved pipe connection from a resiliently mounted compressor within a sealed motor-compressor unit to the exterior of the unit which is resilient to permit a certain amount of movement of the unit relative to its enclosing casing without danger of breaking the rigid connections of the pipe and the movement of which pipe is muflied to eliminate. noises during vibrations thereof,

bottom of the-motor-compressor unit;

Fig. 5 is a horizontal section of the motor compressor unit taken on the line 55 of Fig. 3

and showing the cylinder and piston portion on the line 56 of Fig. 3 showing the refrigerant inlet conduit and chamber construction of the compressor; Fig. 7 is a vertical sectional view through the head of the compressor and istaken on the line 'i-i of Fig. 3; Fig. 8 is a sectional view'- taken on the line 8-8 of Fig. 3 showing the refrigerant inlet valve of the compressor; and

oil separator with respect to the discharge re'- frigerant muflier of the unit.

In carrying out the foregoing objects it is a still further and more specific object ofmy invention to provide an improved structure for and method of separating refrigerant from oil frigerant to operating parts of the unit.

Further objects and advantages reside in the cooperation of parts of the structure which facilitates the manufacture and assembly of my improved motor-compressor unit and in novel combinations and arrangements to provide an Referring to the drawings, for illustrating my invention, I have shown in Figs. 1 and 2 a refrig crating apparatus including a cabinet of the usual household type having a machine compartment to in the lower portion thereof and a plurality of insulated walls H forming or ,surrounding a food storage compartment (not shown) above the machine compartment It. The horizontal frame members E2 of the-cabinet have spaced apart metal crossmembe'rs it secured thereto and upon which a refrigerant liquefying of outwardly extending leg l8 which are bolted;

preferably by resilient rubber mounting devices, to the metal cross members M for supporting the refrigerant liquefying and condensing apparatus within the machine compartment I8 of the refrigerator cabinet. The unit l has a pipe I9 extending therefrom and leading to the condenser |6 for conveying compressed refrigerant from the motor-compressor unit to the condenser.

Compressed refrigerant discharged from unit I5 is cooled and liquefied in the condenser l6 and flows through a pipe 2| to a liquid refrigerant receiver 22. Liquid refrigerant flows from the receiver 22 through a pipe 23 upwardly to an evaporator (not shown) usually located in intimate heat exchange relation with the interior of the food storage compartment of the refrigerator cabinet. The evaporator upon absorbing heat from the food compartment causes liquid refrigerant in the evaporator to vaporize and this gaseous refrigerant is returned to the motorcompressor unit I5 through the pipe 24. The temperature of the evaporator or of the interior of the food compartment, formed by the insulated walls II, is ordinarily controlled bya thermostatically operated switch (not shown) having an electrical connection 26 with a terminal box 2'! provided with lead wires 28 entering the unit l5 by way of terminal 29 and connected with the motor thereof for governing operations of unit I5. v

Since my invention is particularly directed to an improved sealed motor-compressor unit employed in closed refrigerating systems of the type illustrated, reference to Fig. 3 of the drawings is made in order to describe the construction thereof. The unit I5 includes a main spider-like frame 3| provided with a central vertical bore forming a bearing 32 for a shaft 33 disposed therein. Spider-like frame 3| is also provided with a plurality of upstanding wall portions 34 concentric with the shaft bore (see Figs. 3 and 4), and which wall portions have outwardly directed arms 35. The top surface of the bottom portion of main frame 3| is provided with a raised bead 36 which forms a valley3'l around the lower part of shaft bearing portion 32 for a purpose to be hereinafter described. The bottom of frame 3| has a plane surface 38 formed thereon and disposed perpendicularly to the shaft bore. Wall portions 34 receive and support a motor stator generally represented by the reference character 4| and having windings connected by leads 42 through the terminals 29 to wires 28. A motor rotor, generally represented by the reference character 43 and located within the motor stator, is rigidly secured to a metal member 44 such as by being tightly pressed thereon. The member 44 has a central bore which receives the upper end of shaft 33 and is preferably rigidly secured to the shaft by being tightly pressed thereon. Rotation of motor rotor 43, therefore, rotates member 44 and shaft 33 due to the rigid connection of member 44 with rotor 43 and shaft 33. Member 44 is hollowed out to fit over and surround the upper portion of shaft bearing 32;

and a thrust washer 45 is disposed between the tension 49 which has its vertical axis offset hori-' zontally relative to ,the vertical axis ofshaft 33 so as to be rotated around the vertical axis of the shaft bore. The offset shaft extension 49 is adapted to operate parts of the compressor portion of unit l5, and this compressor portion includes a housing 5| having a horizontally disposed cylinder 52 formed therein. Housing 5| has a plane top surface that is secured in sealing engagement to the plane bottom surface 38 of main frame 3| by bolts or the like 53 (see Figs. 4 and 6) A piston 54 located within cylinder 52 is welded or otherwise suitably secured to a hori-' zontally disposed collar-like element 55 provided with aligned elongated openings for receiving the shaft extension 49. A horizontally disposed slider 56 fits within collar 55 and-is provided with a vertical opening which receives the shaft extension 49 and with cylindrical outer Wall surfaces forming a bearing for collar 55 (see Figs. 3 and 5). The construction and arrangement of the elements of the connection between the ofiset shaft extension 49 and piston 54 form what is commonly termed a Scotch yoke connection. The Scotch yoke connection is held in place relative to the shaft extension 49 by virtue of the piston fitting within cylinder 52 formed in housing 5|.

A sheet metal member 58 is located at the outer end of housing 5| and a valve plate 59 and a compressor head 6| are disposed respectively over member 58. Member 58, plate 59 and head 6| are clamped in place upon the outer end of housing 5| by bolts or the like 62. Sheet metal member 58 is provided with an opening which registers with an opening 63 provided in valve plate 59. Member 58 is also provided with a pair of openings 64 (see Fig. 8) which register with a like pair of openings 65 (see Fig-3) provided in the valve plate 59. The sheet metal member 58 is cut out as at 66 (see Fig. 8) to form a valve 61 which covers an inlet port 68 provided in .valve plate 59. Compressor head BI is hollowed out as at 'H to provide communication between the holes 63 and 68 in the valve plate. Head 6| is also hollowed out as at 12 to provide a discharge passage for refrigerant compressed by the compressor piston 54. A reed valve 13 located within the hollowed out part 12 of. compressor head 6| (see Fig. 7) and secured by screws 14 to valve plate 59 covers the discharge opening 65 in plate 59 and is pressed against plate 59 by a spring 15 which surrounds a stud head 6|. A central web 18 (see Fig. '7) provided on, the head 6| partitions the inlet and outlet top end of bearing 32 and the inner surface of passages leading to and from the compressor The chamber or hollowed out partcylinder. 12 of head 6| is provided with an opening 19 in which an end of a pipe 8| is disposed and secured for conveying refrigerant compressed by the compressor therefrom. The upper part of housing 5| is hollowed out as at 83 and 84 (see Fig. 6) to provide two chambers which are separated by a web 85 having a hole 88 therethrough providing communication between the chambers. The outer wall 81 of chamber 84 has a hole 88 therein which is in alignment with the hole provided in member 58 and registering with the hole 63 in valve plate 59 (see Figs. 3 and 6). A pair of bores 89 extending through housing 5| to chamber 83 each have one end of a pair of pipes 9| secured therein,-which pipes are bent upwardly and have their opposite end terminating in the vicinity of the top edge of the upstanding wall portions 34 of main frame 3|.

Pipe 8| extends from the compressor head 6| to-a sheetmetal muflier device generally reprewhich is cut out as at I04 (see Fig. 4)" to provide a plurality of integral depending legs I05. The legs I05 of plate I03 partition the chamber I02 into a plurality of compartments and these legs are cut oil as at I08 to provide'communication between the plurality of compartments within chamber I02. One leg I05a, of the plurality of legs I05 located intermediate the embossed portions 98 and 99, is devoid of the cut off portion I06 (see Fig. 9) and forms a closed partition in r the chamber I02 between the embossed portions 98 and 99 so as to cause refrigerant to flowentirely around the chamber I02. The sheet metal member IOI, top plate 94 and'interm'ediate plate I03 are all welded or otherwise suitably secured together to provide a unitary device. The lower member Il and intermediate plate- I03 of device 92 are provided with a central opening which registers with the opening 95 in the top plate 94. A metal screen I08 in the form of a disc has its edge welded or otherwise suitably secured to the lowermost point of the bottom sheet metal member IOI. Themuflier device 92 is mounted on housing so that the center of openings in member. IM and plate I03 and the center of opening 98 in plate .94 are in vertical alignment.- with the axis of shaft 33 located in the shaft bore of main frame 3I. A hollow inverted coneshaped element III having acover H2 is secured to the eccentric or offset extension 49 of shaft 33 by a screw II3.

, Heat generated by the compressor is transmitted through. piston 54, collar 55, slider 58 and shaft extension 49'to the element 'III to thereby maintain thisjelement at a higher temperature than the body of liquid in the unit for a purpose to be hereinafter described. ,Cover II2 of element III is provided with holes H4 and H5 for a purpose to also be hereinafter described.- The axis of cone-shaped element III is disposed 0 in the vertical plane of the shaft 33, and rotation of the shaft extension 49 around the axis of shaft 33 causes rotation of element III about the same axis of shaft 33. A pipe II5 having its one endsecured to the embossed portion 99 in 55 plate 94 of device 92 has its other end secured to a, connector III sealed to and extending through a wallof a lower casing II8 of the-unit.

[The pipe III; communicates with the pipe I9 through the connector I I] and the portion of pipe IIB intermediate its ends is rendered resilient by being formed-into a @011": I9 having a turn or turns surrounding the compressor of the unit.

In order to prevent 0011 H9 formed by pipe H6 1 from generating or creating noises, due to the 5 resilient mounting of the unit within its sealed casing, as wilI be presently described, I provide the unit and causes same to snub or reduce vibr'ations of the coil II9-to thereby prevent same from creating noisesfduring operation of the unit. Lower casing I I8 of unit. I5 is provided with a connector I which extends through a wall thereof and has the refrigerant pipe 24-secured thereto.

This connector I25 hasga short pipe I26 secured to its inner end and which pipe I 26 is bent so 'as to extend upwardly to a point above the mounting legs 35 of main frame 3| within the unit.

A dome I30 is welded to the lower casing II 8, and this dome and casing provide a sealed enclosurefor the motor-compressor unit I5. I The parts of the motor-compressor are supported from dome I30 by a plurality of resilient mounting devices. Each of these mounting devices'includes a metal bracket I3I welded to the inner upright wall surface of dome I30 and having an --upper horizontal leg I32 and a lower horizontal leg I33. The lowerleg-I33 of bracket I3I is provided with a slot for the reception of a stud I 34 which has a threaded .shank I35 extending through the slotin leg I33 and which shank has a nut I 38 thereon. A clip .I3I is disposed between nut I36 and the bottom surface "of leg I33 of bracket I 3|, and this clip fits around a shouldered portion of the leg I33 and has a part there'- of' bent over so as to engage the nut and lock same in position. 'The upper portion of stud I34 has a spiral groove cut therein for threadably receiving the lower end portion of a coil spring 38. the arm 35 of mainzframe 3| and is provided with an integral depending portion I42. The stud I39 also has a spiral groove cut therein for receiving the upper end portion of spring I38. Thus, spring I38 is: locked between the-main frame 3| and brackets I 3| to resiliently support the motor-compressor within the sealed unit- I5.

A small spring I44 has its convolutions coiled around the wire forming at least one convolution of the compression or supporting spring I38 and its function is to prevent sp ing I39 from generating noise during vibrati thereof when the motor-compressor unit operates. The resilient mounting devices are novel in that the'upper legs I32 of brackets I3I are in the path of upward movement of arms 35 of main frame 3| and these legs I32, therefore, prevent movement when the motor-compressor unit moves sideways relative to the enclosing dome I30 to there.- by snub orcushion horizontal movement of the motor-compressor. The relation of legs I32 of brackets I3I relative to the upper surface of arms,

35 and re'lative'to the upright wall portions 34 of main frame 3| prevents damaging the refrigerant pipe connections within the sealed unit during shipping thereof by virtue of forming a stop for upward and sidewise movement, of the motor-compressor.

The interior of the unit I5 forms a part of the low pressure portion of. the refrigerating A stud I39 hasfa portionl4l threaded into system and is, therefore, under compressor suction pressure. A body of lubricant, preferably heavier than the refrigerant" employed in the system, is contained in the bottom of the sealed enclosure. Lubricant from the body of liquid in the unit is raised by the element III in a manner to be hereinafter described and is caused to flow through a hole I46 drilled through the shaft extension 49 and terminating in communication 'with the lowermost portion of a spiral groove I4'I cut in the surface of shaft 33. Shaft extension 49 is provided with a horizontal hole I48 extending-from hole I46 .to a groove provided aroundthe extension and which groove communicates with horizontally'disposed holes I49, provided in slider 56. A hole II provided in the shaft bearing portion 32 of fram3I permits gall to flow from the shaft bearing surface intothe valley 3'! and into a cavity I52 provided intframe 3| and through a hole: I53 cut in the ,bottom wall of frame 3I'. The opening I53 regmisters with a passage I54 provided in housing 5|,

'- hand this passage I54 directs the oil onto the comapressor piston to lubricate the compressor cyli dnder;

- \When the electric circuit to the motor stator ,,:is.completed, in response to a demand for refri eration within the food compartment of the refrigerator, the stator 4I causes rotation of the motor rotor 43. Rotation of rotor 43 rotates member 44 and shaft 33 to cause rotation of the eccentric shaft extension 49 in a circle around the axis of the shaft 33. This rotation of shaft extension 49 causes reciprocationof slider 50 within the collar-like element 55 during movement of element 55 to and from housing 5| to reciprocate the piston 54 within the cylinder 52. Refrigerant evaporated in the evaporator of the refrigerating system is conveyed through pipe 24, connector I25. and pipe I26 into the interior of the sealed unit; When the piston 54 moves in a direction outwardly of its cylinder 52 during reciprocation thereof, the valve 61 is moved, away from the port 68 and gaseous refrigerant contained in the sealed unit I5 is drawn through the pipes 9I, passages 89, chamber 83, hole 86, chamber 84, holes 08 and 63, chamber II and hole 68 into the cylinder 52. Drawing the gaseous refrigerant through the series of passages and chambers in the structure disclosed reduces suction noises to a minimum without materially terfering with the how of gaseous refrigerant to the cylinder and without loss of efliciency. Upon the return stroke of-piston 54, during its reciprocation, valve 6'1 is caused to close or seal the port 68 whereupon the gaseous refrigerant is compressed in the cylinder 52 and this compressed ing the compressed refrigerant to pass through the plurality of compartments within device 92, noises created by refrigerant being discharged from the compressor are deadened or eliminated. The compressed refrigerant and oil circulated therewith through device 92 enters the pipe IIB, communicating with the outlet thereof, and is directed through the pipe coil H9 and connector III to the exterior of unit I5. Pipe I9 secured to connector II'I conveys the compressed refrigxerant into the condenser I6 where it is cooled turned to unit I5 along with evaporated refrigerant settles to the'bottom of the interior of the unit and accumulates therein in the form of a body of liquid. The-oil inherently contains some refrigerant, and the body of liquid inthe'bottom of the unit is, therefore, somewhat turbulent.

The shape of device 92 together with the screen I08 provides a quiet zone at the center of the interior of unit I5; and it is,.of course, desirable to remove lubricant from the body thereof at this quiet zone. Since the bottom of cone-shaped element III is open and normally projects into the body of liquid in unit I5, rotation of element III, about the vertical axis of rotation of shaft- 33, by rotation of the .shaft extension 49 around the axis of the shaft causes same to elevate liquid from the body thereof. This elevated liquid may be a mixture of refrigerant and oil'and because of the higher temperature of element III the refrlgerant passes into a gaseous state. Then due refrigerant in openings. in member 58 and holes in plate 59 causes valve I3 to be lifted from its seat and permit the compressed refrigerant to flow into thechamber I2 and into the pipe 8|. The compressed refrigerant is directed by pipe 8I into the'device 92 on one side of the,

closed partition I05a within the doughnut-shaped chamber: I02 thereof.. The compressed refrigerant flows from one compartment to another within chamber I02 and beneath the partitions I05 to the outlet chamber on the opposite side of the onepartition I05a. Any oil circulatbd with the compressed refrigerant settles to the bottom of the doughnut-shaped chamber I02 and is forced from one compartment to another of the chamber by-refrigerant flowing through the small passages provided by'the cut-01f parts I06 of legs or partitions I05 to the outlet chamber. By causbearing in the mainframe 3I.

to the speed of rotation of element III, the oil, which is heavier than the refrigerant gas, flows upwardly within the cone-shaped element while the refrigerant separates and flows outwardly of I the element through the aperture or opening I I4 in the center of the top wall thereof. Thus, substantially pure oil or oil devoid of refrigerant clings to the wall of element III and is whirled to the top of the tapered wall thereof where it flows outwardly of element III through the offcenter aperture II5 in its top wall II2. Since aperture II5 communicates with the hole I46 in shaft extension 49, the relatively pure oil is forced upwardly in hole I46 to the horizontal hole I48 in shaft extension 49 and to the spiral groove formed around shaft 33. Rotation of shaft extension 49 causes hole I48 therein to continuously communicate with the opposed holes I48 inslider 56 whereby oil is, fed to thebearing surfaces of the shaft extension 49 with slider 56 and to the bearing surfaces of slider 58 with the collar-like element 55. Oil forced upwardly within hole I46 beyond the moving parts of the Scotch yoke is fed into the spiral groove I41 around shaft 33 and this oil lubricates the shaft Some oil conveyed upwardly within the shaft bearing, by the spiral groove .-I4I,; leaves the bearing surface through opening I5I and flows downwardly to the valley 31 formed in the-upper face of the bottom wall of main frame 3!. A quantity of oil is conveyed by the groove I41 to the top of the shaft bearing and lubricates the bearing surface of thrust washer 45, and its exit therefrom is effected by the'groove or grooves 46formed there-'- in. Oil leaving the bearing surface of the thrust washer 45 flows downwardly around the exterior shaft bearing forming portion 32 of frame 3| and around the inside of the hollowed out portion of member 44 into the valley or trough 31. The valley or trough '31 is preferably inclined and drains the'oil to the cavity I52 where it is cylinder causes oil at one time or another to be drawn toward the cylinder around the piston for lubricating same. The oil thendrops into the body of liquid in the bottom of the unit where 7 it is contained prior to again being separated from refrigerant and forced through the bearing l0 surfaces of operating parts of the unit.

' From the foregoing, it will be apparent'that I have provided an improved sealed motor-compressor'unit for a refrigerating system which has novel structural features for effecting quiet and efficient operation of the unit. The muiiler device in the present structure-substantially eliminates noise of refrigerant being compressed and discharged from the compressor and, by disposing 'same in the body of liquid. in the bottom of the unit, the heat of compressed refrigerant flowing therethrough causes refrigerant to evaporate from thebody of liquid to thus maintain the liquid richer" in oil consistency. This feature, together with the fact that refrigerant is further separated from oil before the oil is circulated to operating parts of the unit, affords a systemof lubrication with substantially pure oil which is important to the life of the unit. The provisionof oilingthe shaft bearing continuously from its'bottom to its top, of oiling the bearing surface of the thrust washer and the compressor piston insures long'life of the unit. The provision of grooves in the bearing surface of the thrust washer for facilitating lubrication thereof and for removing oil therefrom permits the escape 'of any refrigerant that may be carried into the shaft bearing along with the oil, and thus prevents this refrigerant from forming a lock which might otherwise block-the flow of oil to the upper part of the shaft bearing and thrust washer bearing surface. The grooves in the bearing surface of the thrust washer also prevent the occurrence of intermittent differential in pressure within the shaft bearing to thereby eliminate noises which might otherwise occur by up and down movement of the shaft relative to .the end of the shaft bearing.

While the form of embodiment'of the invention as herein disclosed, constitutes a preferred 50 supported therefrom, said casing'being under compressor suction pressure, refrigerant conveying means having a connection with said'compressor and a connection with said casing, said" means including a device carried by said motorcompressor for receiving and mufiling refrigerant discharged from said compressor, said means also including a pipe having an end secured to said device and having its other end secured to said casing for directing refrigerant discharged from said compressor to the exterior of said unit, said pipe being in the form of a coil and having a convolution thereof extending around said compressor to provide the pipe with a resilient portion intermediate its secured ends, and means abutting said compressor and applying force to said resilient intermediate convolution portion of the pipe coil at a plurality of widely spaced apart means interposed between said compressor and said pipe coil permitting up and down movement w 5 points for preventing same from generating audible sounds.

2. A sealed unit comprising, a casing having a motor and a compressor directly connected to said motor disposed therein andbeing resiliently supported therefrom, said casing being under compressor suction pressure, refrigerant conveying means having a connection with said compressor and a connectionv with said casing, said means including a device carried by said'motorcompressor for receiving and mufiling refrigerant discharged from said compressor, said means also including a pipe having an end secured to said device and having its other end secured to said I casing for directing refrigerant discharged from said compressorto the exterior of said unit, said pipe being in the form of a coil and having a convolution thereof extending around said compressor to provide the pipe with a resilient portion intermediate its secured ends, and spring of the coil relative to said casing, said spring means having its central portion abutting'said compressor and having its e'nds straddling and applying force to said pipe coil convolution at a plurality of widely spaced apart points for preventing same fromgenerating audible sounds.

3. A sealedmotor-compressor unit including a Y 'wcasing under compressor suction pressure, a main frame within said casing supporting said motorcompressor therefrom, said main frame having a vertical bore forming an elongated bearing, a shaft within said bore, a motor stator carried by said frame and a motor rotor secured to the upper end-of said shaft for rotating same, a

plane surface on said frame perpendicular to the bore therein, a compressor secured to saidplane surface of said main frame and depending therefrom, said compressor comprising a housing hay. I,

ing a cylinder formed therein, a piston within said cylinder, said shaft having an offset por-,

tion depending below said frame and connected with said piston for'reciproca'ting same within said cylinder during rotation of said shaft, the portion of said compressor housing secured to said planesurface of said frame being hollowed out to form' with said plane surface walls of a plurality of closed chambers, said closed chambers being incommunication with one another and with the inlet to said compressor, means communicating with the interior of said unit and with one of said chambers whereby refrig erant is directed first through one of said plu rality of chambers and thence through another thereof to the inlet of said compressor for mufsaid frame and a motor rotor secured to the upper face on said frame perpendicular to thebore therein, a compressor secured to said plane surface of said main frame and depending therefrom, said compressor comprising a housing having a cylinder formed therein with an axis perpendicular to the axis of said shaft, a piston within said pending below said frame and connected to said piston for reciprocating same within said cylinder during rotation of said shaft, the portion of said compressor housing secured to said frame plane surface being hollowed out to form with said plane surface walls of horizontally spaced apart closed chambers, the one chamber disposed nearest to the axis of said shaft communicating with the other chamber and with the interior of said unit, the said other chamber communicating with the inlet to said compressor whereby refrigerant is directed through said one chamber and thence through said other chamber to the inletof saidcompressor for muiiiing the flow of refrigerant into the compressor cylinder, and a closed refrigerant conduit for conveying refrigerant discharged from said compressor exteriorly of said unit.

5. A sealed unit comprising, a casing having a motor and a compressor directly connected to said motor disposed therein and being resiliently supported therefrom, said casing being under compressor suction pressure, refrigerant conveying means having a connection with said compressor and a connection with said casing, said means including a pipe for directing refrigerant discharged from said compressor to the exterior of said unit, said pipe being in the form of a coil and having a convolution thereof extending around said compressor to provide the pipe with a resilient portion intermediate the compressor and said casing, means interposed between said compressor and said pipe coil, and said last named means contacting said resilient intermediate convolution portion of the pipe coilat a plurality of spaced apart points and applying force thereto for preventing same from generating audible sounds.

6. A sealed unit comprising a casing having a motor and a compressor directly connected to said motor disposed therein and being resiliently supported therefrom, said casing being under compressor suction pressure, refrigerant conveying means having a connection with said compressor and a connection with said casing, said means including a pipe for directing refrigerant discharged from said compressor to the exterior of said unit, said pipe being in the form of a coil and having a convolution thereof extending around said compressor to provide the pipe with a resilient portion intermediate the compressor and said casing, means interposed between said compressor and said pipe coil, a spring member frictionally interposed between said compressor and said pipe coil, and said spring member contacting said resilient intermediate convolution portion of the pipe coil at a plurality of widely spaced apart points to apply force thereto for preventing same from generating audible sounds. 7. A sealed unit comprising, a casing having a motor and a compressor directly connected to said motor disposed therein and being resiliently supported therefrom, a refrigerant conveying conduit having a connection with said compressor and a connection with said casing, said conduit being of such length as to provide same with a flexible portion intermediate the compressor and said casing to permit limited movement of the compressor relativeto the casing, and sound dampening means comprising a resilient member for applying force transversely to said flexible portion of said conduit.

8. A sealed unit comprising, a casing having a motor and a compressor directly connected to said motor disposed therein, a plurality of resilient means supporting the motor-compressor within said casing, each of said means including a coiled compression spring disposed in a vertical plane and supporting. the weight of said motor-compressor, and each of said means also including a wire-like coil spring having its convolutions coiled around at least a part of a convolution of said first named spring whereby the axis of said last named spring substantially coincides with the axis of the wire forming said first named spring.

. -ROLF M. SMITH. 

